Preheat the oven to 150°C and line two large baking sheets with parchment paper.

In a food processor, pulse the coconut, 1/3 cup of the sugar, and cornstarch until finely ground.

In the bowl of a standing electric mixer fitted with the whisk attachment, beat the egg whites and salt at medium-high speed until firm peaks form.

Gradually add the remaining 2/3 cup of sugar, 1 tablespoon at a time, while beating until the mixture is stiff and glossy.

Gently fold in the coconut mixture.

Transfer the meringue to a pastry bag fitted with a 1.

5 cm star tip.

Pipe 4 cm mounds of meringue onto the baking sheets, spacing them about 3 cm apart.

Sprinkle each meringue with chopped pistachios.

Bake for 25 minutes, rotating the baking sheets from top to bottom and front to back halfway through baking, until the meringues are slightly browned and set but still soft inside.